Was there any warning sign from more than one month ago? It seems rather sudden. dtp has been around for quite a while and has a good library of adventure games. Was this a sale issue or something else?

I have seen no warning sign or anything like this that dtp was about to close its doors. However, games these days are big busines and a game needs to sell at least 1 million copies to be succesfull. And by that I mean to break even, e.g. just getting the money back investors poured into making the game.

Most rpgs these days need to sell at least 2 million copies to break even or more. My guess is that dtp didn't get enough enough income to make some payment either on loans or maybe even on wages/salaries for their employees.